EP2431660B1

EP2431660B1 - Lamp device

Info

Publication number: EP2431660B1
Application number: EP11153747A
Authority: EP
Inventors: Kyung-Il Kong
Original assignee: LG Innotek Co Ltd
Current assignee: LG Innotek Co Ltd
Priority date: 2010-09-17
Filing date: 2011-02-08
Publication date: 2012-11-07
Anticipated expiration: 2031-02-08
Also published as: KR101742678B1; KR20120029632A; EP2431660A1; US20110204764A1; CN102410515B; EP2511606A1; US8476813B2; JP2012064562A; JP2016042492A; EP2511606B1; JP5868622B2; JP6196330B2; CN102410515A

Description

Field

This embodiment relates to a lamp device.

Description of the Related Art

A light emitting diode (LED) is an energy device converting electric energy into light energy and has low power consumption, a semi-permanent life span, a rapid response speed, safeness and environment-friendliness as compared with existing light sources like a fluorescent light, an incandescent lamp and the like.
Therefore, many researches are devoted to substitution of the existing light sources with the LED. The LED is now increasingly used as a light source for lighting devices, for example, a liquid crystal display device, an electric sign, a street lamp, a pilot lamp, a room lamp and the like.
Such lighting devices are disclosed in US2009/0257234 A1 , JP 2002 367 406 A and EP 2 206 945 A1 .

SUMMARY

In this embodiment, it is possible to effectively radiate heat generated by operating a lamp device.
In this embodiment, when there are problems in the parts of the lamp device, it is possible to easily repair and maintain the problems.
In this embodiment, it is possible to improve the installation flexibility without a spatial limitation by reducing the volume of the lamp device.
One embodiment is a lamp device includes:

a heat radiating body comprising a structure and a plurality of fins, wherein the structure comprises an inner surface and an outer surface such that an opening is formed and wherein a plurality of the fins extend to the outside from the outer surface of the structure; and
a substrate being under a plurality of the fins of the heat radiating body and comprising a plurality of light emitting devices disposed on one side thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of a lamp device according to an embodiment of the present invention.
Fig. 2 is a perspective view of a cross section of the lamp device according to the embodiment shown in Fig. 1 of the present invention.
Fig. 3 is an exploded perspective view of a lamp device according to the embodiment shown in Fig. 1 of the present invention.
Fig. 4 is a perspective view of another lamp device according to an embodiment of the present invention.
Fig. 5 is an exploded perspective view of the lamp device according to the embodiment shown in Fig. 4 of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

A thickness or size of each layer is magnified, omitted or schematically shown for the purpose of convenience and clearness of description. The size of each component does not necessarily mean its actual size.
It will be understood that when an element is referred to as being 'on' or "under" another element, it can be directly on/under the element, and one or more intervening elements may also be present. When an element is referred to as being 'on' or 'under', 'under the element' as well as 'on the element' can be included based on the element.
Hereinafter, an embodiment will be described with reference to the accompanying drawings.
Fig. 1 is a perspective view of a lamp device according to an embodiment of the present invention. Fig. 2 is a perspective view of a cross section of the lamp device according to the embodiment shown in Fig. 1 of the present invention. Fig. 3 is an exploded perspective view of a lamp device according to the embodiment shown in Fig. 1 of the present invention.
Referring to Figs. 1 to 3, a lamp device 100 according to an embodiment of the present invention includes a heat radiating body 110, a substrate 130, a light source unit 150, a light guider 170, a flange 190, a first member 210, a condensing lens 220, a second member 230 and a fixing member 250.
The heat radiating body 110 is formed by organically coupling a ring structure 111, a plurality of fins 113 and a flat portion 115, so that the heat radiating body 110 has a shape of a donut. However, the shape of the heat radiating body 110 is not limited to this. For example, the heat radiating body 110 may have a polygonal shape or other various shapes.
The ring structure 111 has an inner surface and an outer surface such that an opening G1 having a central axis "A" is formed in the center of the ring structure 111. A plurality of the fins 113 are joined to the outer surface of the ring structure 111 and radially extend to the outside from the outer surface of the ring structure 111. A plurality of the fins 113 may be separated from each other at a regular interval such that heat generated from a light source unit 150 which will be described below is wholly uniformly radiated to the outside. The flat portion 115 is joined to one end of the outer surface of the ring structure 111 and extends perpendicular to the outer surface of the ring structure 111. The flat portion 115 is joined to one ends of a plurality of the fins 113 joined to the outer surface of the ring structure 111.
The substrate 130 includes a top surface and a bottom surface. The top surface comes in surface contact with the flat portion 115 of the heat radiating body. The light source unit 150 is disposed on the bottom surface. It is desirable that a commonly used metal printed circuit board (PCB) is mainly used as the substrate 130. However, any substrate capable of including the light source unit can be used as the substrate 130.
The substrate 130 has a disk shape for sealing the ring structure 111 having the opening G1. In addition, the substrate 130 is required to have an opening G2 in the center thereof in order that heat generated from the light source unit 150 can be radiated to the outside through the circulation of the air. The opening G2 at the center of the substrate is placed corresponding to the opening G1 of the heat radiating body such that they have the same central axis ``A". Here, it is required that the opening G2 at the center of the substrate and the opening G1 of the heat radiating body have the same area for the purpose of improving the assemblability and heat radiating characteristic of the lamp device.
The light source unit 150 includes a plurality of light emitting diodes (LEDs). A plurality of the LEDs are radially disposed on the bottom surface of the substrate. That is, a plurality of the LEDs may be disposed on the bottom surface of the substrate 130 at a regular interval just like a plurality of the fins 113 are disposed.
As such, when a plurality of the LEDs are radially disposed on the substrate, the radiation area of heat generated from the operation of the LEDs becomes greater, so that heat release efficiency is improved. The heat from the LEDs is radiated through the surface contact between the flat portion of the heat radiating body and the top surface of the substrate and through a plurality of the fins of the heat radiating body, As a result, heat radiating surface area is increased so that a heat transfer characteristic is improved.
Though not shown in the drawings, a conductive sheet for radiating heat is further added between the substrate 130 and the flat portion 115 of the heat radiating body 110, so that it is possible to enhance the heat transfer characteristic between the substrate 130 and the heat radiating body 110.
Since a plurality of the LEDs are mounted and disposed on one substrate instead of separate substrates, if necessary, it is possible to easily repair and maintain the substrate including the light source unit.
The light guider 170 includes a plurality of optical fibers. One end of each optical fiber is optically connected to a plurality of the LEDs 150. In the present embodiment, though the optical fiber is taken as an example of the light guider 170, any device like a prism of an optical device capable of changing the direction of light generated by the light source unit into a desired direction can be used as the light guider 170.
The flange 190 includes a plurality of holes 191 for inserting and binding the ends of a plurality of the optical fibers, and has an entire shape of a disk. Therefore, a plurality of the LEDs are bound by the flange 190, so that a wide emission area of light generated from a plurality of the radially disposed LEDs becomes smaller. As a result, the light is collected in a particular direction.
The ends of the optical fibers inserted into the holes 191 of the flange 190 are aligned with the holes 191 of the flange such that the ends are placed on the same plane. This intends to obtain the uniform intensity of light at a particular plane on which the light is incident. The flange is seated in an opening G3 of the first member 210 which will be described below, so that the flange has an optical orientation plane according to the adjustment of the angle of the first member 210.
The first member 210 includes a first projection 212, a second projection 213 and a first ring structure 211 having an inner surface and an outer surface such that a circular opening G3 having a central axis is formed in the center of the first ring structure 211. The first projection 212 and the second projection 213 are formed on the outer surface of the first ring structure 211 to face each other. The first projection 212 and the second projection 213 extend from the outer surface of the first ring structure 211 to the outside. The first projection 212 and the second projection 213 of the first member 210 are inserted into a first hole 231a and a second hole 231b of the second member 230, which are described below, respectively. Accordingly, the first member 210 is joined and fixed to the second member 230.
The first member 210 is inclined at an angle to rotate about the first projection 212 and the second projection 213. Therefore, light generated from the light source unit 150 can be directed to a direction that a user desires by through adjustment of the angle of the first member 210.
The condensing lens 220 is optically joined to the first member 210 and covers the opening opposite to the first member's circular opening in which the flange 190 is seated. Such a condensing lens more optically condenses the light which has been physically condensed by the flange.
Like the first member 210, the second member 230 includes a first projection 232, a second projection 233 and a second ring structure 231 having an inner surface and an outer surface such that a circular opening G4 having a central axis is formed in the center of the second ring structure 231. The second member 230 includes the first hole 231a and the second hole 231b into which the first and the second projections 212 and 213 of the first member 210 are inserted. The first hole 231a and the second hole 231b penetrate the inner and outer surfaces of the second ring structure 231 and face each other. The first and the second projections 232 and 233 extend from the outer surface of the second ring structure 231 to the outside.
In such a second member 230, a first imaginary line horizontally extending from the first projection 232 to the second projection 233 is at a right angle to a second imaginary line extending from the central axis of the first hole 231 a to the central axis of the second hole 231b.
The circumferential extent of the inner surface of the second member 230 is greater than that of the outer surface of the first member 210, so that the first member 210 is inserted into the second member 230.
The fixing member 250 includes an inner circumferential portion 251 such that a circular opening G5 having a central axis of the inner circumferential portion 251 is formed, an outer circumferential portion 253 formed along the inner circumferential portion at a regular interval from the inner circumferential portion 251, and flat portion 255 extending vertically from the end of the inner circumferential portion to the end of the outer circumferential portion.
The inner circumferential portion 251 of the fixing member 250 includes mutually facing first and second holes 251a and 251b into which the first projection 232 and the second projection 233 are inserted. The first projection 232 and the second projection 233 of the second member 230 are respectively inserted into the first hole 251a and the second hole 251b of the fixing member 250. The second member 230 is joined and fixed to inner surface of the inner circumferential portion 251 of the fixing member 250.
The outer circumferential portion 253 of the fixing member 250 surrounds the light source unit 150 and the light guider 170.
Since the lamp device mentioned above includes a heat radiating body having a structure in which the heat generated from the light emitting diodes can be radiated spatially not in an up-and-down direction but in a horizontal direction when the lamp device is operated, the entire volume of the lamp device can be actually reduced. Accordingly, as compared with a conventional heat radiating body radiating heat in the up-and-down direction, the heat radiating body of the present invention has a lower spatial limitation when the lamp device is installed. As a result, installation flexibility can be improved.
Fig. 4 is a perspective view of another lamp device according to an embodiment of the present invention. Fig. 5 is an exploded perspective view of the lamp device according to the embodiment shown in Fig. 4 of the present invention.
Referring to Figs. 4 to 5, another lamp device 300 according to one embodiment of the present invention includes a heat radiating body 310, a heat radiating plate 330, a substrate 350, a light source unit 370, a light guider 390, a flange 410, a first member 430, a second member 450 and a fixing member 470.
The heat radiating body 310 is formed by organically coupling a ring structure 311 and a plurality of fins 313, so that the heat radiating body 310 has a shape of a donut. However, the shape of the heat radiating body 310 is not limited to this. For example, the structure 311 may have a polygonal shape or other various shapes. The ring structure 311 has an inner surface and an outer surface such that an opening G1' having a central axis "A" is formed in the center of the ring structure 311. A plurality of the fins 313 which are joined to the outer surface of the ring structure 311 and radially extend to the outside from the outer surface of the ring structure 311. A plurality of the fins 313 are separated from each other at a regular interval such that heat generated from a light source unit 370 which will be described below is wholly uniformly radiated to the outside. That is, two adjacent fins may be spaced apart from each other at a regular interval.
The heat radiating plate 330 includes a hole 331 located at an area corresponding to the interval between the two adjacent fins among a plurality of the fins 313, and contacts with a plurality of the radially disposed fins 313. The heat radiating plate 330 also includes a central opening G2' placed corresponding to the central opening G1' of the heat radiating body 310. The hole 331 of the heat radiating plate 330 has a rectangular shape which is actually parallel with the longitudinal direction of the fin such that the external air more easily flows in from the top of the heat radiating body. When the substrate directly contacts with a plurality of the fins of the heat radiating body, the heat radiating plate 330 may be omitted. If the heat radiating plate 330 is integrally formed with the heat radiating body 310, the heat radiating body 110 shown in Fig. 3 can be actually formed. In other words, the heat radiating plate 330 is able to function as the flat portion 115 of the heat radiating body 110 shown in Fig. 3.
The substrate 350 includes a top surface and a bottom surface. The top surface comes in surface contact with the heat radiating plate 330. The light source unit 370 is disposed on the bottom surface. It is desirable that a commonly used metal printed circuit board (PCB) is mainly used as the substrate 350. However, any substrate capable of including the light source unit can be used as the substrate 350.
The substrate 350 has a disk shape for sealing the heat radiating plate 330 having the opening G2'. In addition, the substrate 350 is required to have an opening G3' in the center thereof in order that heat generated from the light source unit 370 can be radiated to the outside through the circulation of the external air. Here, the opening G3' at the center of the substrate 350 is placed corresponding to the opening G2' of the heat radiating plate 330. Additionally, the substrate 350 includes a plurality of holes 351. A plurality of the holes 351 are placed between the light source units 370 which will be disposed on the bottom surface of the substrate.
It is more desirable that the holes of the substrate are disposed between the light source units 370 and correspond to the holes 331 of the heat radiating plate 330. Like the hole 331 of the heat radiating plate 330, the hole 351 of the substrate has also a rectangular shape.
Though not shown in the drawings, the substrate 350 is able to directly contact with a plurality of the fins of the heat radiating body and transfer heat without the heat radiating plate. It is possible to improve the heat transfer characteristic between the heat radiating body and the heat radiating plate or between the heat radiating plate and the substrate by adding a conductive sheet between the heat radiating body and the heat radiating plate or between the heat radiating plate and the substrate.
The light source unit 370 includes a plurality of light emitting diodes (LEDs). A plurality of the LEDs are radially disposed on the bottom surface of the substrate. That is, a plurality of the LEDs are disposed on the bottom surface of the substrate 350 just like a plurality of the fins 313 of the heat radiating body 310 are disposed.
As such, when a plurality of the LEDs are radially disposed on the substrate, the radiation area of heat generated from the operation of the LEDs becomes greater, so that heat release efficiency is improved. The heat from the LEDs can be radiated by the circulation of the air through the holes of either the substrate or the heat radiating plate. A plurality of the fins of the heat radiating body increase the heat radiation surface area, so that a heat transfer characteristic is improved. Though not shown in the drawings, a conductive sheet for radiating heat is further added between the substrate and the heat radiating plate, so that it is possible to enhance the heat transfer characteristic between the substrate and the heat radiating plate.
Since a plurality of the LEDs are mounted and disposed on one substrate instead of separate substrates, if necessary, it is possible to easily repair and maintain the substrate including the light source unit.
Since the light guider 390, the flange 410, the first member 430, a condensing lens 440, the second member 450 and the fixing member 470 are similar to those of the one embodiment of the present invention, the descriptions thereof will be omitted.
The features, structures and effects and the like described in the embodiments are included in at least one embodiment of the present invention and are not necessarily limited to one embodiment. Furthermore, the features, structures and effects and the like provided in each embodiment can be combined or modified in other embodiments by those skilled in the art to which the embodiments belong. Therefore, the contents related to the combination and modification should be construed to be included in the scope of the present invention.
The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. The description of the foregoing embodiments is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures.

Claims

A lamp device comprising:
a heat radiating body (310) comprising a structure (311) and a plurality of fins (313), wherein the structure (311) comprises an inner surface and an outer surface such that an opening (G1') is formed and wherein the plurality of the fins (313) extend to the outside from the outer surface of the structure (311) ; and

a substrate (350) being under the plurality of the fins (313) of the heat radiating body (310) and comprising a plurality of light emitting devices (370) disposed on one side thereof, characterized in that the substrate (350) comprises holes (351) between the plurality of the light emitting devices (370).
The lamp device of claim 1, wherein the substrate (350) comprises an opening (G3') formed such that the opening (G3') corresponds to the opening (G1') of the heat radiating body (310).
The lamp device of claim 2, wherein the opening (G1') of the heat radiating body (310) and the opening (G3') of the substrate (350) have the same central axis.
The lamp device of claim 1, wherein the structure (311) has a ring shape.
The lamp device of claim 1, further comprising a heat radiating plate (330) being located between the substrate (350) and the plurality of the fins (313) of the heat radiating body (310), and having an opening (G2') corresponding to the opening (G1') of the heat radiating body (310), wherein the heat radiating plate (330) comes in surface contact with the substrate (350).
The lamp device of claim 5, wherein the heat radiating body (310) is integrally formed with the heat radiating plate (330).
The lamp device of claim 5 or claim 6, wherein two adjacent fins (313) among the plurality of the fins of the heat radiating body (310) are spaced apart from each other at a predetermined interval, wherein the heat radiating plate (330) comprises a hole (331) located at an area corresponding to the interval between the two fins (313), and wherein one side of the heat radiating plate (330) contacts with the plurality of the fins.
The lamp device of claim 7, where the hole (331) of the heat radiating plate (330) has a rectangular shape which is actually parallel with the longitudinal direction of the fin.
The lamp device of claim 1, further comprising a plurality of optical fibers of which one ends are optically connected to a plurality of the light emitting devices (370) respectively.
The lamp device of claim 9, wherein the other ends of the optical fibers of the plurality of the optical fibers are bound to each other.
The lamp device of claim 1, wherein the plurality of the fins (313) of the heat radiating body (310) are separated from each other at a regular interval.
The lamp device of claim 1 or claim 5, wherein the plurality of the fins (313) of the heat radiating body (310) directly contact with one side of the substrate (350).
The lamp device of claim 1, wherein the plurality of the light emitting devices (370) are radially disposed on one side of the substrate (350).
The lamp device of claim 1 or claim 13, wherein the plurality of the light emitting devices (370) are disposed at a regular interval on the one side of the substrate (350).